- Annoying Video-Game Helper: Jessica has a tendency to attract gunfire from enemies without any provocation from the player.
- Awesome Music: Emergence's theme song.
- The anime adaptation, Si N: The Movie, also has an amazing orchestra soundtrack composed by Masamichi Amano.
- Base-Breaking Character: JC, your Mission Control. He's either dorky and amusing, or annoying and grating in your ear throughout the entire original game. Interestingly, even those who weren't fans of him generally seem to agree that his Sudden Sequel Death Syndrome in the animated movie was pointlessly stupid and soured it almost right out of the gate.
- Best Known for the Fanservice: Elexis Sinclaire, who is known to even people who never played the games.
- Complete Monster:
- Elexis Sinclaire is the seductive Overarching Villain of the series, and the current CEO of SinTEK Enterprises. An Evilutionary Biologist even as a kid, Elexis plans to turn humanity into destructive mutants as a way to unlock mankind's ultimate genetic potential, all as a form of scientific progress. Creating the drug U4 that turns people into mutants, she has it sold around Freeport, while also kidnapping homeless people and random civilians and forcing them to undergo painful transformations. Ordering gangster Antonio Mancini to steal a safety deposit box from the bank's vault, she forcibly transforms him into a mutant after he fails and gains the attention of HardCorps agent Col. John Blade. She has her troops try and dump U4 into the Freeport water system, which would turn the city into mutants. Once that fails, Elexis steals a bunch of nuclear warheads and plans to insert U4 into them, preparing to launch them onto various parts of the world, hoping to convert the entire Earth into mutants. Despite her father curing her of a disease, she keeps him as a giant attack mutant, and later has Blade fight him. Making a getaway, she returns in SiN Episodes: Emergence to start her plan again, where she rigs a laboratory to explode, inserts mutant DNA into Blade and Jessica Cannon, and prepares to unleash her mutants onto Freeport.
- SiN: Wages of Sin Expansion Pack: Gianni Manero is a psychopathic, power-hungry mob boss who desires the destruction of Freeport city. Using Elexis Sinclaire's SinTek mutants, he forces Sinclaire's head scientist to work for him by holding his daughter hostage. He's altered the U4 drug to not only control the mutants directly, but also transform humans into hundreds of giant Goliath mutants. When he discovers that John Blade's after him, he lures him to his lab and tries to have him killed by his Goliaths, and once that fails, he rigs the facility to detonate, then tries to destroy Freeport's offshore nuclear power plant, planning to start a chain reaction that will cause Freeport to explode, preparing to kill not only 10 million people, but himself too.
- Evil Is Sexy: Elexis Sinclaire. She's as vile as she is sexualized.
- "Oh Noisy One Kenobi."
- One of the mutants that Blade kills in The Movie dies a Rasputinian Death in about seven seconds, as its head is blown apart, it falls and gets impaled on a spire as High-Pressure Blood flies everywhere (including on the camera), and then near-instantly explodes into a raging fire geyser. The whole thing's so over the top and spontaneous, it's like a parody of itself.
- Obvious Beta: The original game was a mess when it first hit shelves. Problems included Loads and Loads of Loading, non-functioning AI for one of the bosses, music tracks not playing correctly (or at all), various game crashes, and typos on various textures. By the time these issues had been patched out, the damage had already been done; the game had released merely two weeks before Valve's mega-hit Half-Life, and SiN was completely overshadowed by that game's runaway success.
- Porting Disaster: The Steam re-release of the original game included with Emergence is a downplayed example. While it was updated to natively support modern computer hardware and use Steam's server browser for multiplayer, the music playback suffers from bugs, has censored nudity and drug references, as well as having edited a number of textures to remove pop-culture references and, oddly, replaced others with renders of Emergence's 3D models. It also does not include the Wages of Sin expansion pack, which itself included several fixes (such as adding several options to the controls menu that were missing in the original for unknown reasons) and allows playing the original campaign with some of the expansion's new additions like dual-wielding the pistol. As of early 2020, however, Nightdive Studios has updated the game to bring it up to snuff with the GOG.com version, including bringing back the original uncensored textures and adding the Wages of SiN expansion, and with promises of a full remaster down the line.
- Scrappy Mechanic: The Personal Challenge System in Emergence. Besides the Game-Breaking Bug on the main page, the difficulty system was meant to scale up select fights throughout the game depending on how well you played. However, whether by poor design or without realizing it, the game counted all enemies in the equation - including random filler foes you're meant to slaughter like cannon fodder in between the major fights the system actually affected. The result was that the system would invariably scale up the game to ridiculous levels with no way to really scale it down, resulting in later encounters becoming almost unplayably difficult.
- That One Level: The climb up the exterior of Supremacy Tower at the end of Sin Episodes is insanely harder than the rest of the game, as you're progressing through massive waves of Elite Mooks in an environment with almost no cover and limited movement due to walking on a narrow ledge over a several hundred foot drop.
- Video Game Movies Suck: A direct-to-video anime movie based off the game was made by ADV Films in 2000. It is remembered by few, and by most accounts liked by even fewer.
- What an Idiot!: Just to give a good example of how infamous the anime movie was, it starts out with the funeral of JC, a character whose entire role in the series was Mission Control and didn't accompany Blade on any field-ops whatsoever. Because on the one time in the franchise he does go with Blade and another Hardcorps soldier, he sticks his arm into mutant goop without even a second thought. Invariably, this led to transforming into a mutant and getting put down by Blade. Did we mention this is the first five minutes of the movie, without any time to characterize him as The Smart Guy?
YMMV / SiN